1. Field
The present invention relates to a printed circuit board, and in particular, to a printed circuit board having embedded electronic components and manufacturing method thereof.
2. Description of the Related Art
Recently, the size of electro components is becoming smaller, and the demand is increasing for high-end products that provide various functions in single packages. In order to meet these desires of consumers, components which had hitherto been attached on the surface of a substrate are being embedded inside the substrate. However, such embedding techniques bring about the problem of cost increase, and this cost increase has to be compensated with improvements in electrical characteristics and miniaturization. Thus, an inexpensive embedding technique is required in order to stimulate the commercialization of the built-in board.
Until now, most embedding techniques have been applied to wafer level packages, in which bumps made of gold or copper are distributed in an area array type over the entire surface of the chip, because it is difficult to perform laser processing after having the chip embedded in the aluminum pads of a thin (about 1 μm thickness) thickness generally used as the chip finish metal. However, as to the area array type, the overall package price is raised, due to the expenses in rewiring and forming metal bumps.
FIG. 1 is a cross-sectional view of a PCB having an embedded chip according to prior art, where a chip 22 having electrode bumps 27 is embedded inside the core board 23.
Conventionally, an operation of forming the electrode bumps on the pads of the chip was performed in order to embed the chip as shown the FIG. 1, which was generally performed by foreign companies. Therefore, the bumping process incurred additional cost and time.